Abstract: 【Abstract】Objectives To explore the effects of seasonal changes on peritoneal dialysis-associated peritonitis (PDAP) in the coastal area of southern China. Methods A retrospective analysis was conducted in the PDAP patients treated during 1st January, 2014 to 31st December, 2020. They were divided into four groups based on the four seasons. OnEway ANOVA and chi square test were used to compare the incidence of PDAP and clinical indexes among the four groups. Pearson correlation analysis was used to analyze the relationship between the incidence of PDAP and climate factors, including monthly mean temperature, humidity and rainfall in the coastal area of southern China. The pathogens of PDAP were also compared among the four groups. Results A total of 323 PDAP episodes in the 178 patients (0.24 episodes/risk year) were recorded during the follow-up period of 6 years. There was no significant difference in the incidence of PDAP among the four groups (χ2=0.019, P=0.995). The incidence of PDAP also had no correlations with monthly mean temperature (r=0.226，P=0.479), monthly mean humidity (r=- 0.180, P=0.576), and monthly mean rainfall (r=0.070, P=0.828). Gram-positive bacteria caused more than half (51.4%) of the PDAP, especially in summer. Gramnegative bacteria were found higher in PDAP in autumn than in other seasons. However, the component of
bacterial pathogens was similar among the four groups (χ2=19.004, P=0.088). Conclusion The incidence of PDAP had no correlations with the four seasons, monthly mean temperature, monthly mean humidity and monthly mean rainfall, and the bacterial pathogens of PDAP also had no correlations with the four seasons in CAPD patients in the coastal area of southern China. More investigations are required to explore the risk factors for PDAP.

Key words: Peritoneal dialysis-associated peritonitis, Climate feature, Distribution of pathogenic bacteria